Fluctuating dermatoglyphic asymmetry: genetic and prenatal influences.

Genetic and environmental prenatal factors influencing the fluctuating asymmetry of the a-b interdigital ridge count are examined. From the results obtained we can conclude that fluctuating asymmetry of the a-b interdigital ridge count is poorly influenced by genetic factors. We suggest that fluctuating asymmetry of dermatoglyphics provides a good measure of developmental stability in humans, especially for males. The results also indicate that random environmental factors, acting before the 19th week of embryonic development, could be related to the differential timing of maturation of the sexes.